Effect of interlayer and deposition temperature on the hydrogen storage properties of amorphous Mg-based thin films

In this work, the effect of different interlayers (including Mo, Nb, and Ti) and deposition temperatures (including 25 °C, 75 °C, 150 °C and 200 °C) on the hydrogen storage performance of MgNi amorphous alloy films are studied. On the one hand, the MgNi amorphous alloy films remain undestroyed after hydrogen absorption and desorption cycles with the help of Mo, Nb and Ti interlayers. However, the onset desorption temperature and peak desorption temperature of the MgNi amorphous alloy films are almost unchanged after inserting the interlayers. On the other hand, as the deposition temperature increases from 25 °C to 200 °C, there are nanocrystalline Mg2Ni and Mg phases formed in the amorphous MgNi alloy matrix. The crystalline-amorphous structure provides abundant nucleation sites for hydride formation, and accelerate the diffusion and dissociation of hydrogen.